Thermodynamics of Na3Cr2(AsO4)3 with garnet structure

Abstract

In this work the heat capacity $C_{p,m}^o=f\left(T\right)$ of the garnet-structured Na₃Cr₂(AsO₄)₃ was first investigated. Measurements were performed in the range of T = (5 and 323) K using a precise adiabatic vacuum calorimeter. The phase purity and composition homogeneity were verified by X-ray diffraction analysis with Rietveld method calculations and X-ray microanalysis. The $C_{p,m}^o,{\Delta }_0^T{H}_m^0,{\Delta }_0^T{S}_m^{0}and{\Delta }_0^T{G}_m^0$ have been calculated using experimental data from T→0 to 323 K.